I’m trying to keep strings after the second underscore and before dot. Thanks!
x <- "Exche_log_group_2.csv", "Exche_log_group_3.csv"
Desired output:
group_2 group_3
>Solution :
use gsub
gsub("[^_]+_[^_]+_|\\..*", "", x)
[1] "group_2" "group_3"